Recent years brought substantial progress in research on imperfect-information games. Superhuman performance has been achieved in large-scale variants of poker. Game theoretic models with all sorts of uncertainty have been applied in security domains ranging from protecting critical infrastructure through green security (for example, protecting wildlife and fisheries) to cyber security. Computer agents able to play a previously unknown imperfect-information games only based on a formal description of its dynamics have been developed.In this AAAI-18 workshop, we aim to create a forum where researchers studying theoretical and practical aspects of imperfect-information games can meet, present their recent results and discuss their new ideas. Moreover, we want to facilitate interaction between distinct communities studying various aspect and focusing on various domains in imperfect information games.